This invention relates to a burster or detacher for detaching form sets from continuous business form assemblies.
A form burster typically has included a pair of low speed rollers through the nip of which a continuous form assembly is fed, followed by a pair of high speed rollers from the nip of which burst form sets exit. The form sets have been burst from the form assembly along transverse perforation lines, by the snap action caused when the leading, unburst form set is accelerated upon entry into the nip of the high speed rollers. Breaker bars and knuckles have been provided to assist bursting along the transverse perforation lines. One such bar has had eccentric knuckles.
Some form bursters have been dedicated to particular form lengths. Others have been adjustable, through lengthening or shortening of the distance between the high speed rollers and the low speed rollers. In an unusual burster, adjustment has been provided by movement of the breaker bar.
Neither dedicated nor adjustable bursters have proven wholly satisfactory. While adjustable bursters are preferred for their versatility, they have been disfavored for their bulkiness and the complexity of construction and operation associated with movement of the roller drives.